On PHPMaster.com there's a new tutorial about array operators in PHP, more so how the usual operators interact with arrays.

Operators in PHP can be organized into seven different categories: arithmetic, assignment, bitwise, comparison, error control, execution, incrementing/decrementing, logical, string, array, and type operators. This article details working with array operators, but also covers how some of the other operators work when used with arrays.

They talk about the operators for:

array union (plus)

equality (double equals)

identity (triple equals)

They also talk briefly about some of the other PHP operators with arrays (like subtraction, multiplication and division) and some of the conversions that PHP does when they're used.

On the MaltBlue.com blog Matthew Setter has a new post about the ZendDbSql component of Zend Framework 2, specifically related to making easy joins and unions. This is the second part of his series on this component.

In the first part of this series on ZendDbSqlSelect, we jumped the gun a bit and went straight in to looking at building Where clauses. We looked at a number of the predicates that are available to us, such as In, Between and EqualTo and saw just how easy ZendDbSqlSelect makes both building and maintaining queries. In this, the second part, we're backtracking a bit and looking at Joins and a slightly more esoteric feature of SQL - UNIONs. By the end of today's tutorial, you'll be building some pretty good queries that should satisfy most of your daily requirements.

He starts with a look at joins, showing in several code examples the various kinds - inner, outer, left and right (as well as self joins). He then moves on to unions, intersects and excerpts with examples of each.

Fresh from Adam Khoury's massive library of instructional videos comes a four-part, full-fledged tutorial on searching a MySQL database using PHP. The tutorials use the 'worked example' format (like Khan Academy), which makes learning relatively painless for newbies and not completely useless for more experienced developers.

The four videos require you to have at least a decent working knowledge of putting PHP and MySQL together and show you how to: